GB1357562A - Addressable gas-discharge devices - Google Patents

Abstract

1357562 Gas discharge display panels FUJITSU Ltd 10 Aug 1971 [10 Aug 1970] 37582/71 Heading H1D Display apparatus comprises a gas discharge panel with insulating walls 21, 22 carrying electrodes 19, 20 and crossed conductor arrays 16, 17 and circuitry connected to the arrays operable to produce cyclotron resonance of electrons to establish a glow discharge at any selected conductor intersection, by producing at that intersection crossed magnetic and microwave electric fields. The panel includes continuous electrodes 19, 20 insulating plates 13, 14 and ferromagnetic films 18 on which the conductors 16, 17 are mounted. A microwave signal is applied across electrodes 19, 20 and a potential is applied to selected conductors. The potential is such that the resulting current and magnetic field produce an electron rotational frequency equal to the frequency of the microwave signal. Under these conditions cyclatron resonance occurs and the microwave power required to initiate a discharge is 1/100 that required if the magnetic field has other values, hence a discharge occurs at selected intersections. The variation of power required with field is very great hence the field due to current in one conductor alone is insufficient to produce a discharge. Moreover a discharge remains localized since charged particles are not given any net movement parallel to the plates 13, 14. The discharge can be maintained with the same microwave power but a lower field hence lower sustaining currents can be applied thereby producing a memory effect. The discharge is erased by further reducing the field. Sustaining D.C. current can be applied to all of the conductors and discharges produced and erased by positive and negative pulses. In other embodiments the sheet electrode is replaced by a strip electrode extending in zig-zag or serpentine fashion over plate 13; the electrodes 16, 17 are on the outside of plates 13, 14 and electrodes 19, 20 on the inside, the latter may be replaced by crossed conductor arrays.